Enzyme catalysis in the presence of ionic liquids

Abstract

The invention relates to the implementation of enzyme-catalysed reactions in the presence of ionic liquids.

1 . A method for the conversion of substances in the presence of enzymes as a catalyst in a reaction medium comprising at least one ionic liquid, wherein the enzyme is selected from the group of oxidoreductases, lipases, galactosidases, glycosidases, lyases and enzymes in EC class 6.  
     
     
         2 . The method according to  claim 1 , characterized in that the ionic liquid has the general formula  
       [Al n   + [Y] n− ,  
       where 
 n=1 or 2 and  
 the anion [Y] n−   0  is selected from the group comprising tetrafluoroborate ([BF 4 ]), tetrachloroborate ([BCl 4 ] − ), hexafluorophosphate ([PF 6 ] − ), hexafluoroantimonate ([SbF 6 ] − ), hexafluoroarsenate ([AsF 6 ] − ), tetrachloroaluminate ([AlCl 4 ] − ), trichlorozincate (ZnCl 3 ] − ), dichlorocuprate, sulphate ([SO 4 ] 2− ), carbonate ([CO 3 ] 2− ), fluorosulphonate, [R′—COO] − , [R′—SO 3 ] −  or [(R′—SO 2 ) 2 N] − , and R′ is a linear or branched aliphatic or alicyclic alkyl containing 1 to 12 carbon atoms or a C 5 -C 18 -aryl, C 5 -C 18 -aryl-C 1 -C 6 -alkyl or C 1 -C 6 -alkyl-C 5 -C 18 -aryl radical that can be substituted by halogen atoms,  
 the cation [A] +  is selected from 
 quaternary ammonium cations having the general formula  
 [NR 1 R 2 R 3 R] + ,  
 phosphonium cations having the general formula  
 [PR 1 R 2 R 3 R] + ,  
 imidazolium cations having the general formula  
                     
  where the imidizole nucleus can be substituted with at least one group selected from C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, C 1 -C 6 -aminoalkyl, C 5 -C 12 -aryl or C 5 -C 12 -aryl-C 1 -C 6 -alkyl groups,  
 pyridinium cations having the general formula  
                     
  where the pyridine nucleus can be substituted with at least one group selected from C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, C 1 -C 6 -aminoalkyl, C 5 -C 12 -aryl or C 5 -C 12 -aryl-C 1 -C 6 -alkyl groups,  
 pyrazolium cations having the general formula  
                     
  where the pyrazole nucleus can be substituted with at least one group selected from C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, C 1 -C 6 -aminoalkyl, C 5 -C 12 -aryl or C 5 -C 12 -aryl-C 1 -C 6 -alkyl groups,  
 and triazolium cations having the general formula  
                     
  where the triazole nucleus can be substituted with at least one group selected from C 1 -C 6 -alkyl, C 1 -C 6 -alkoxy, C 1 -C 6 -aminoalkyl, C 5 -C 12 -aryl or C 5 -C 12 -aryl-C 1 -C 6 -alkyl groups,  
  and the radicals R 1 , R 2 , R 3  are selected independently of one another from the group consisting of 
 hydrogen;  
 linear or branched, saturated or unsaturated, aliphatic or alicyclic alkyl groups with 1 to 20 carbon atoms;  
 heteroaryl, heteroaryl-C 1 -C 6 -alkyl groups with 3 to 8 carbon atoms in the heteroaryl radical and at least one heteroatom selected from N, O and S which can be substituted with at least one group selected from C 1 -C 6 -alkyl groups and/or halogen atoms;  
 aryl-, aryl-C 1 -C 6 -alkyl groups with 5 to 12 carbon atoms in the aryl radical which if necessary can be substituted with at least one C 1 -C 6 -alkyl group and/or one halogen atom.  
 
 
 
     
     
         3 . The method according to any one of the preceding claims, characterised in that the fraction of the ionic liquid in the reaction medium is 0.1 to 99.9 percent by volume.  
     
     
         4 . The method according to any one of the preceding claims, characterised in that in addition to the ionic liquid, the reaction medium also contains a further solvent.  
     
     
         5 . The method according to any one of the preceding claims, characterized in that the further solvent is water or an organic solvent.  
     
     
         6 . The method according to any one of the preceding claims, characterised in that the reaction is carried out at temperatures of −10° C. to 130° C.  
     
     
         7 . The method according to any one of the preceding claims, characterised in that the reaction is carried out in a single-phase fashion or in a multiphase reaction system.  
     
     
         8 . A composition comprising an enzyme selected from the groups of oxidoreductases, lipases, galactosidases, glycosidases, lyases and enzymes in EC class 6 and at least one ionic liquid.  
     
     
         9 . The composition according to claim a, characterised in that the ionic liquid is defined as in  claim 2 .  
     
     
         10 . The composition according to  claim 8  or  claim 9 , characterised in that it additionally contains a substrate.  
     
     
         11 . The composition according to any one of  claims 8  to  10 , characterised in that it contains the ionic liquid as a reaction medium or as a constituent of the reaction medium.  
     
     
         12 . Use of ionic liquids as a reaction medium or as a constituent of the reaction medium for enzymatically catalysed reactions, wherein the enzyme is selected from the group of oxidoreductaaes, lipases, galactosidases, glycosidases, lyases and enzymes in EC class 6.  
     
     
         13 . The use according to  claim 12  as a reaction medium or as a constituent of the reaction medium in reverse hydrolysis for the synthesis of di- and oligosaccharides.